1. Field of Invention
The invention concerns a device for gripping and transporting at least one ink-attracting cylinder of a printing machine in which the device includes support elements that enter into contact with pins of the cylinder in order to be able to raise the cylinder, in which each support element includes at least two gripper arms, with which a pin of the cylinder can at least be partially gripped, a first gripper arm being movable between an open position and a closed position in which the pin is gripped, and a second gripper arm being fixed. The invention also relates to an ink-attracting cylinder and a method for gripping and transporting at least one cylinder.
2.Description of the Prior Art
It is often necessary to change the rolls of a printing machine for completion of print jobs. Most often the actual printing cylinders are generally changed, since they carry the medium that ensures the print pattern on the stock. Such printing cylinders generally include a cylinder body and a pin on each of its ends. The surface of the cylinder body is available for the medium, which is glued, for example, to the cylinder body or fastened on a sleeve, which is then pushed onto the cylinder body, while the pins are provided especially for supporting of the cylinder in the printing machine. If such a cylinder is to be changed, it is also gripped via the pins.
The present invention, however, does not pertain merely to printing cylinders, but to all cylinders in a printing machine that attract ink. In particular, these can be anilox rollers. For example, anilox rollers in a flexographic printing machine serve to apply printing ink to the printing cylinders. Anilox rollers can also be replaced, for example, when the printing ink is changed in the corresponding inking system.
In a central cylinder flexographic printing machine the inking systems are generally arranged around a central impression cylinder. Each inking system then includes at least one printing cylinder, which can be set against the impression cylinder carrying the stock. The anilox roller can again be set against the printing cylinder, which removes the printing ink that it transfers to the printing cylinder from an ink reservoir, for example, a doctor blade chamber. Machines are also known in which an ink coating roller is connected between the ink reservoir and the anilox roller.
Printing machines that operate according to other printing methods include additional and/or other cylinders than those described for flexographic printing.
In order to be able to set the different rollers and cylinders against each other, each of them is mounted with its pins in a bearing element that can be moved relative to the printing machine frame. In the example of flexographic printing this bearing element is often a bearing block that can be moved on guides. These guides and the bearing block are arranged on or against brackets of the printing machine frame.
In order to be able to change the cylinders a system for gripping and transporting at least one ink-attracting cylinder is provided in printing machines of the prior art, which can take up the pins that pass through the elements from the ends. Support elements are configured for this purpose so that the pins lie on them. The support elements are then arranged on a movement device which in turn is arranged on a support frame and can be moved relative to it. The movement device is configured so that the support elements can be moved past the bracket of the printing machine frame on the outside in order to be able to grip the pins from the outside. Publication EP 1 016 522 A1 shows such a system. Cylinders with pins on the end are also often referred to as print rolls.
Gripping of the pins from the end, however, means that a large space on both sides of the printing machine is required for the gripping and transport system.
The task of the invention is therefore to propose an improved system that gets by with a smaller space.